1. Field of the Invention
The present invention relates to an AND (logical product) circuit and more particularly, to an AND circuit to which an input differential signal is inputted.
2. Description of the Related Art
In the following Patent document 1, an AND circuit in which differential pairs of transistors are stacked vertically is described. In general, a two-input AND circuit outputs an AND signal of first and second input signals. When both the first and the second input signals are at the LOW level, the output signal is at the LOW level. When the first input signal is at the LOW level and the second input signal is at the HIGH level, the output signal is at the LOW level. When the first input signal is at the HIGH level and the second input signal is at the LOW level, the output signal is at the LOW level. When both the first and the second outputs are at the HIGH level, the output signal is at the HIGH level. In FIG. 3 in Patent document 1, a circuit in which a diode is provided in an AND circuit including two differential pairs stacked vertically is shown.
(Patent Document 1) Japanese Patent Application Laid-open No. Hei 2-246615.